PlayerPrefs help !

Hi,

I tried in very much ways, but I really can't figure it out. This is a level lock/unlock system made by me. On my PC works perfectlly, but when I test it on my android smartphone nothing works. Why ? If I will use PlayerPrefs will work ? How I should use PlayerPrefs ? Because I tried in very much ways and no result.

Here is my script:

 using UnityEngine;
 using System.Collections;
 
 public class LevelLockSystem : MonoBehaviour {
 
     public GameObject unlockLevel2;
     public GameObject unlockLevel3;
     public GameObject unlockLevel4;
     public GameObject unlockLevel5;
     public GameObject unlockLevel6;
     public GameObject unlockLevel7;
     public GameObject unlockLevel8;
     public GameObject unlockLevel9;
     public GameObject unlockLevel10;
 
     public void Start()
     {
         
     }
 
     public void LockAllLevels()
     {
         unlockLevel2.SetActive(true);
         unlockLevel3.SetActive(true);
         unlockLevel4.SetActive(true);
         unlockLevel5.SetActive(true);
         unlockLevel6.SetActive(true);
         unlockLevel7.SetActive(true);
         unlockLevel8.SetActive(true);
         unlockLevel9.SetActive(true);
         unlockLevel10.SetActive(true);
     }
     public void UnlockLevel2()
     {
         unlockLevel2.SetActive(false);
     }
     public void UnlockLevel3()
     {
         unlockLevel3.SetActive(false);
     }
     public void UnlockLevel4()
     {
         unlockLevel4.SetActive(false);
     }
     public void UnlockLevel5()
     {
         unlockLevel5.SetActive(false);
     }
     public void UnlockLevel6()
     {
         unlockLevel6.SetActive(false);
     }
     public void UnlockLevel7()
     {
         unlockLevel7.SetActive(false);
     }
     public void UnlockLevel8()
     {
         unlockLevel8.SetActive(false);
     }
     public void UnlockLevel9()
     {
         unlockLevel9.SetActive(false);
     }
     public void UnlockLevel10()
     {
         unlockLevel10.SetActive(false);
     }
 
 }